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petsc_matrix.cc
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			/**
			* @file petsc_matrix.cc
			*
			* @author Aurelia Isabel Cuba Ramos <aurelia.cubaramos@epfl.ch>
			*
			* @date creation: Mon Dec 13 2010
			* @date last modification: Fri Aug 21 2015
			*
			* @brief Implementation of PETSc matrix class
			*
			* @section LICENSE
			*
			* Copyright (©) 2010-2012, 2014, 2015 EPFL (Ecole Polytechnique Fédérale de
			* Lausanne) Laboratory (LSMS - Laboratoire de Simulation en Mécanique des
			* Solides)
			*
			* Akantu is free software: you can redistribute it and/or modify it under the
			* terms of the GNU Lesser General Public License as published by the Free
			* Software Foundation, either version 3 of the License, or (at your option) any
			* later version.
			*
			* Akantu is distributed in the hope that it will be useful, but WITHOUT ANY
			* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
			* A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
			* details.
			*
			* You should have received a copy of the GNU Lesser General Public License
			* along with Akantu. If not, see <http://www.gnu.org/licenses/>.
			*
			*/

			/* -------------------------------------------------------------------------- */
			#include "petsc_matrix.hh"
			#include "static_communicator.hh"
			#include "static_communicator_mpi.hh"
			#include "mpi_type_wrapper.hh"
			#include "dof_synchronizer.hh"
			#include "petsc_wrapper.hh"
			/* -------------------------------------------------------------------------- */
			#include <cstring>
			#include <petscsys.h>

			__BEGIN_AKANTU__

			#if not defined(PETSC_CLANGUAGE_CXX)
			int aka_PETScError(int ierr) {
			CHKERRQ(ierr);
			return 0;
			}
			#endif

			// struct PETScWrapper {
			// Mat mat;
			// AO ao;
			// ISLocalToGlobalMapping mapping;
			// /// pointer to the MPI communicator for PETSc commands
			// MPI_Comm communicator;
			// };

			/* -------------------------------------------------------------------------- */
			PETScMatrix::PETScMatrix(UInt size,
			const SparseMatrixType & sparse_matrix_type,
			const ID & id,
			const MemoryID & memory_id) :
			SparseMatrix(size, sparse_matrix_type, id, memory_id),
			petsc_matrix_wrapper(new PETScMatrixWrapper),
			d_nnz(0,1,"dnnz"),
			o_nnz(0,1,"onnz"),
			first_global_index(0),
			is_petsc_matrix_initialized(false) {
			AKANTU_DEBUG_IN();
			StaticSolver::getStaticSolver().registerEventHandler(*this);
			this->offset = 0;
			this->init();

			AKANTU_DEBUG_OUT();
			}

			/* -------------------------------------------------------------------------- */
			PETScMatrix::PETScMatrix(const SparseMatrix & matrix,
			const ID & id,
			const MemoryID & memory_id) :
			SparseMatrix(matrix, id, memory_id),
			petsc_matrix_wrapper(new PETScMatrixWrapper),
			d_nnz(0,1,"dnnz"),
			o_nnz(0,1,"onnz"),
			first_global_index(0),
			is_petsc_matrix_initialized(false) {
			// AKANTU_DEBUG_IN();
			// StaticSolver::getStaticSolver().registerEventHandler(*this);
			// this->offset = 0;
			// this->init();

			// AKANTU_DEBUG_OUT();
			AKANTU_DEBUG_TO_IMPLEMENT();
			}

			/* -------------------------------------------------------------------------- */
			PETScMatrix::~PETScMatrix() {
			AKANTU_DEBUG_IN();

			/// destroy all the PETSc data structures used for this matrix
			this->destroyInternalData();
			StaticSolver::getStaticSolver().unregisterEventHandler(*this);

			AKANTU_DEBUG_OUT();
			}

			/* -------------------------------------------------------------------------- */
			void PETScMatrix::init() {
			AKANTU_DEBUG_IN();

			/// set the communicator that should be used by PETSc
			#if defined(AKANTU_USE_MPI)
			StaticCommunicator & comm = StaticCommunicator::getStaticCommunicator();
			const StaticCommunicatorMPI & mpi_st_comm =
			dynamic_cast<const StaticCommunicatorMPI &>(comm.getRealStaticCommunicator());
			this->petsc_matrix_wrapper->communicator = mpi_st_comm.getMPITypeWrapper().getMPICommunicator();
			#else
			this->petsc_matrix_wrapper->communicator = PETSC_COMM_SELF;
			#endif

			PetscErrorCode ierr;

			/// create the PETSc matrix object
			ierr = MatCreate(this->petsc_matrix_wrapper->communicator, &(this->petsc_matrix_wrapper->mat)); CHKERRXX(ierr);


			/**
			* Set the matrix type
			* @todo PETSc does currently not support a straightforward way to
			* apply Dirichlet boundary conditions for MPISBAIJ
			* matrices. Therefore always the entire matrix is allocated. It
			* would be possible to use MATSBAIJ for sequential matrices in case
			* memory becomes critical. Also, block matrices would give a much
			* better performance. Modify this in the future!
			*/

			ierr = MatSetType(this->petsc_matrix_wrapper->mat, MATAIJ); CHKERRXX(ierr);

			this->is_petsc_matrix_initialized = true;


			AKANTU_DEBUG_OUT();
			}

			/* -------------------------------------------------------------------------- */
			/**
			* With this method each processor computes the dimensions of the
			* local matrix, i.e. the part of the global matrix it is storing.
			* @param dof_synchronizer dof synchronizer that maps the local
			* dofs to the global dofs and the equation numbers, i.e., the
			* position at which the dof is assembled in the matrix
			*/
			void PETScMatrix::setSize() {
			AKANTU_DEBUG_IN();

			PetscErrorCode ierr;

			/// find the number of dofs corresponding to master or local nodes
			UInt nb_dofs = this->dof_synchronizer->getNbDOFs();
			UInt nb_local_master_dofs = 0;

			/// create array to store the global equation number of all local and master dofs
			Array<Int> local_master_eq_nbs(nb_dofs);
			Array<Int>::scalar_iterator it_eq_nb = local_master_eq_nbs.begin();

			/// get the pointer to the global equation number array
			Int * eq_nb_val = this->dof_synchronizer->getGlobalDOFEquationNumbers().storage();

			for (UInt i = 0; i <nb_dofs; ++i) {
			if (this->dof_synchronizer->isLocalOrMasterDOF(i) ) {
			*it_eq_nb = eq_nb_val[i];
			++it_eq_nb;
			++nb_local_master_dofs;
			}
			}

			local_master_eq_nbs.resize(nb_local_master_dofs);

			/// set the local size
			this->local_size = nb_local_master_dofs;

			/// resize PETSc matrix
			#if defined(AKANTU_USE_MPI)
			ierr = MatSetSizes(this->petsc_matrix_wrapper->mat, this->local_size, this->local_size, this->size, this->size); CHKERRXX(ierr);
			#else
			ierr = MatSetSizes(this->petsc_matrix_wrapper->mat, this->local_size, this->local_size); CHKERRXX(ierr);
			#endif

			/// create mapping from akantu global numbering to petsc global numbering
			this->createGlobalAkantuToPETScMap(local_master_eq_nbs.storage());


			AKANTU_DEBUG_OUT();
			}

			/* -------------------------------------------------------------------------- */
			/**
			* This method generates a mapping from the global Akantu equation
			* numbering to the global PETSc dof ordering
			* @param local_master_eq_nbs_ptr Int pointer to the array of equation
			* numbers of all local or master dofs, i.e. the row indices of the
			* local matrix
			*/
			void PETScMatrix::createGlobalAkantuToPETScMap(Int* local_master_eq_nbs_ptr) {
			AKANTU_DEBUG_IN();

			PetscErrorCode ierr;

			StaticCommunicator & comm = StaticCommunicator::getStaticCommunicator();
			UInt rank = comm.whoAmI();

			//initialize vector to store the number of local and master nodes that are assigned to each processor
			Vector<UInt> master_local_ndofs_per_proc(nb_proc);

			/// store the nb of master and local dofs on each processor
			master_local_ndofs_per_proc(rank) = this->local_size;



			/// exchange the information among all processors
			comm.allGather(master_local_ndofs_per_proc.storage(), 1);

			/// each processor creates a map for his akantu global dofs to the corresponding petsc global dofs

			/// determine the PETSc-index for the first dof on each processor

			for (UInt i = 0; i < rank; ++i) {
			this->first_global_index += master_local_ndofs_per_proc(i);
			}

			/// create array for petsc ordering
			Array<Int> petsc_dofs(this->local_size);
			Array<Int>::scalar_iterator it_petsc_dofs = petsc_dofs.begin();

			for (Int i = this->first_global_index; i < this->first_global_index + this->local_size; ++i, ++it_petsc_dofs) {
			*it_petsc_dofs = i;
			}

			ierr = AOCreateBasic(this->petsc_matrix_wrapper->communicator, this->local_size, local_master_eq_nbs_ptr, petsc_dofs.storage(), &(this->petsc_matrix_wrapper->ao)); CHKERRXX(ierr);

			AKANTU_DEBUG_OUT();
			}

			/* -------------------------------------------------------------------------- */
			// void PETScMatrix::createLocalAkantuToPETScMap(const DOFSynchronizer & dof_synchronizer) {
			// AKANTU_DEBUG_IN();

			// AKANTU_DEBUG_ASSERT(this->petsc_matrix_wrapper->ao != NULL,
			// "You should first create a mapping from the global"
			// << " Akantu numbering to the global PETSc numbering");

			// PetscErrorCode ierr;

			// this->dof_synchronizer = &const_cast<DOFSynchronizer &>(dof_synchronizer);

			// /// get the number of dofs
			// Int nb_dofs = dof_synchronizer.getNbDOFs();

			// /// get the global equation numbers for each node
			// Array<Int> global_dof_equation_numbers = dof_synchronizer.getGlobalDOFEquationNumbers();

			// /// map the global dof equation numbers to the corresponding PETSc ordering
			// ierr = AOApplicationToPETSc(this->petsc_matrix_wrapper->ao, nb_dofs,
			// global_dof_equation_numbers.storage()); CHKERRXX(ierr);

			// /// create the mapping from the local Akantu ordering to the global PETSc ordering
			// ierr = ISLocalToGlobalMappingCreate(this->petsc_matrix_wrapper->communicator,
			// 1, nb_dofs, global_dof_equation_numbers.storage(),
			// PETSC_COPY_VALUES, &(this->petsc_matrix_wrapper-mapping)); CHKERRXX(ierr);

			// AKANTU_DEBUG_OUT();
			// }

			/* -------------------------------------------------------------------------- */
			/**
			* This function creates the non-zero pattern of the PETSc matrix. In
			* PETSc the parallel matrix is partitioned across processors such
			* that the first m0 rows belong to process 0, the next m1 rows belong
			* to process 1, the next m2 rows belong to process 2 etc.. where
			* m0,m1,m2,.. are the input parameter 'm'. i.e each processor stores
			* values corresponding to [m x N] submatrix
			* (http://www.mcs.anl.gov/petsc/).
			* @param mesh mesh discretizing the domain we want to analyze
			* @param dof_synchronizer dof synchronizer that maps the local
			* dofs to the global dofs and the equation numbers, i.e., the
			* position at which the dof is assembled in the matrix
			*/

			void PETScMatrix::buildProfile(const Mesh & mesh, const DOFSynchronizer & dof_synchronizer, UInt nb_degree_of_freedom) {
			AKANTU_DEBUG_IN();

			//clearProfile();
			this->dof_synchronizer = &const_cast<DOFSynchronizer &>(dof_synchronizer);
			this->setSize();
			PetscErrorCode ierr;

			/// resize arrays to store the number of nonzeros in each row
			this->d_nnz.resize(this->local_size);
			this->o_nnz.resize(this->local_size);

			/// set arrays to zero everywhere
			this->d_nnz.set(0);
			this->o_nnz.set(0);


			// if(irn_jcn_to_k) delete irn_jcn_to_k;
			// irn_jcn_to_k = new std::map<std::pair<UInt, UInt>, UInt>;

			coordinate_list_map::iterator irn_jcn_k_it;

			Int * eq_nb_val = dof_synchronizer.getGlobalDOFEquationNumbers().storage();
			UInt nb_global_dofs = dof_synchronizer.getNbGlobalDOFs();
			Array<Int> index_pair(2);

			/// Loop over all the ghost types
			for (ghost_type_t::iterator gt = ghost_type_t::begin(); gt != ghost_type_t::end(); ++gt) {
			const GhostType & ghost_type = *gt;
			Mesh::type_iterator it = mesh.firstType(mesh.getSpatialDimension(), ghost_type, _ek_not_defined);
			Mesh::type_iterator end = mesh.lastType (mesh.getSpatialDimension(), ghost_type, _ek_not_defined);
			for(; it != end; ++it) {
			UInt nb_element = mesh.getNbElement(*it, ghost_type);
			UInt nb_nodes_per_element = Mesh::getNbNodesPerElement(*it);
			UInt size_mat = nb_nodes_per_element * nb_degree_of_freedom;

			UInt * conn_val = mesh.getConnectivity(*it, ghost_type).storage();
			Int * local_eq_nb_val = new Int[nb_degree_of_freedom * nb_nodes_per_element];


			for (UInt e = 0; e < nb_element; ++e) {
			Int * tmp_local_eq_nb_val = local_eq_nb_val;
			for (UInt i = 0; i < nb_nodes_per_element; ++i) {
			UInt n = conn_val[i];
			for (UInt d = 0; d < nb_degree_of_freedom; ++d) {
			/**
			* !!!!!!Careful!!!!!! This is a ugly fix. @todo this is a
			* very ugly fix, because the offset for the global
			* equation number, where the dof will be assembled, is
			* hardcoded. In the future a class dof manager has to be
			* added to Akantu to handle the mapping between the dofs
			* and the equation numbers
			*
			*/

			tmp_local_eq_nb_val++ = eq_nb_val[n nb_degree_of_freedom + d] - (dof_synchronizer.isPureGhostDOF(n * nb_degree_of_freedom + d) ? nb_global_dofs : 0);

			}
			}


			for (UInt i = 0; i < size_mat; ++i) {
			Int c_irn = local_eq_nb_val[i];
			UInt j_start = 0;
			for (UInt j = j_start; j < size_mat; ++j) {
			Int c_jcn = local_eq_nb_val[j];
			index_pair(0) = c_irn;
			index_pair(1) = c_jcn;
			AOApplicationToPetsc(this->petsc_matrix_wrapper->ao, 2, index_pair.storage());
			if (index_pair(0) >= first_global_index && index_pair(0) < first_global_index + this->local_size) {
			KeyCOO irn_jcn = keyPETSc(c_irn, c_jcn);
			irn_jcn_k_it = irn_jcn_k.find(irn_jcn);

			if (irn_jcn_k_it == irn_jcn_k.end()) {
			irn_jcn_k[irn_jcn] = nb_non_zero;


			// check if node is slave node
			if (index_pair(1) >= first_global_index && index_pair(1) < first_global_index + this->local_size)
			this->d_nnz(index_pair(0) - first_global_index) += 1;
			else
			this->o_nnz(index_pair(0) - first_global_index) += 1;
			nb_non_zero++;

			}
			}

			}

			}
			conn_val += nb_nodes_per_element;
			}

			delete [] local_eq_nb_val;
			}
			}



			// /// for pbc @todo correct it for parallel
			// if(StaticCommunicator::getStaticCommunicator().getNbProc() == 1) {
			// for (UInt i = 0; i < size; ++i) {
			// KeyCOO irn_jcn = key(i, i);
			// irn_jcn_k_it = irn_jcn_k.find(irn_jcn);
			// if(irn_jcn_k_it == irn_jcn_k.end()) {
			// irn_jcn_k[irn_jcn] = nb_non_zero;
			// irn.push_back(i + 1);
			// jcn.push_back(i + 1);
			// nb_non_zero++;
			// }
			// }
			// }



			// std::string mat_type;
			// mat_type.resize(20, 'a');
			// std::cout << "MatType: " << mat_type << std::endl;
			// const char * mat_type_ptr = mat_type.c_str();
			MatType type;
			MatGetType(this->petsc_matrix_wrapper->mat, &type);
			/// std::cout << "the matrix type is: " << type << std::endl;
			/**
			* PETSc will use only one of the following preallocation commands
			* depending on the matrix type and ignore the rest. Note that for
			* the block matrix format a block size of 1 is used. This might
			* result in bad performance. @todo For better results implement
			* buildProfile() with larger block size.
			*
			*/
			/// build profile:
			if (strcmp(type, MATSEQAIJ) == 0) {
			ierr = MatSeqAIJSetPreallocation(this->petsc_matrix_wrapper->mat,
			0, d_nnz.storage()); CHKERRXX(ierr);
			} else if ((strcmp(type, MATMPIAIJ) == 0)) {
			ierr = MatMPIAIJSetPreallocation(this->petsc_matrix_wrapper->mat,
			0, d_nnz.storage(), 0,
			o_nnz.storage()); CHKERRXX(ierr);
			} else {
			AKANTU_DEBUG_ERROR("The type " << type << " of PETSc matrix is not handled by"
			<< " akantu in the preallocation step");
			}

			//ierr = MatSeqSBAIJSetPreallocation(this->petsc_matrix_wrapper->mat, 1,
			// 0, d_nnz.storage()); CHKERRXX(ierr);

			if (this->sparse_matrix_type==_symmetric) {
			/// set flag for symmetry to enable ICC/Cholesky preconditioner
			ierr = MatSetOption(this->petsc_matrix_wrapper->mat, MAT_SYMMETRIC, PETSC_TRUE); CHKERRXX(ierr);
			/// set flag for symmetric positive definite
			ierr = MatSetOption(this->petsc_matrix_wrapper->mat, MAT_SPD, PETSC_TRUE); CHKERRXX(ierr);
			}
			/// once the profile has been build ignore any new nonzero locations
			ierr = MatSetOption(this->petsc_matrix_wrapper->mat, MAT_NEW_NONZERO_LOCATIONS, PETSC_TRUE); CHKERRXX(ierr);

			AKANTU_DEBUG_OUT();
			}


			/* -------------------------------------------------------------------------- */
			/**
			* Method to save the nonzero pattern and the values stored at each position
			* @param filename name of the file in which the information will be stored
			*/
			void PETScMatrix::saveMatrix(const std::string & filename) const{
			AKANTU_DEBUG_IN();

			PetscErrorCode ierr;

			/// create Petsc viewer
			PetscViewer viewer;
			ierr = PetscViewerASCIIOpen(this->petsc_matrix_wrapper->communicator, filename.c_str(), &viewer); CHKERRXX(ierr);

			/// set the format
			PetscViewerSetFormat(viewer, PETSC_VIEWER_DEFAULT); CHKERRXX(ierr);
			/// save the matrix
			/// @todo Write should be done in serial -> might cause problems
			ierr = MatView(this->petsc_matrix_wrapper->mat, viewer); CHKERRXX(ierr);

			/// destroy the viewer
			ierr = PetscViewerDestroy(&viewer); CHKERRXX(ierr);

			AKANTU_DEBUG_OUT();
			}

			/* -------------------------------------------------------------------------- */
			/**
			* Method to add an Akantu sparse matrix to the PETSc matrix
			* @param matrix Akantu sparse matrix to be added
			* @param alpha the factor specifying how many times the matrix should be added
			*/
			void PETScMatrix::add(const SparseMatrix & matrix, Real alpha) {
			PetscErrorCode ierr;
			// AKANTU_DEBUG_ASSERT(nb_non_zero == matrix.getNbNonZero(),
			// "The two matrix don't have the same profiles");

			Real val_to_add = 0;
			Array<Int> index(2);
			for (UInt n = 0; n < matrix.getNbNonZero(); ++n) {
			UInt mat_to_add_offset = matrix.getOffset();
			index(0) = matrix.getIRN()(n)-mat_to_add_offset;
			index(1) = matrix.getJCN()(n)-mat_to_add_offset;
			AOApplicationToPetsc(this->petsc_matrix_wrapper->ao, 2, index.storage());
			if (this->sparse_matrix_type == _symmetric && index(0) > index(1))
			std::swap(index(0), index(1));

			val_to_add = matrix.getA()(n) * alpha;
			/// MatSetValue might be very slow for MATBAIJ, might need to use MatSetValuesBlocked
			ierr = MatSetValue(this->petsc_matrix_wrapper->mat, index(0), index(1), val_to_add, ADD_VALUES); CHKERRXX(ierr);
			/// chek if sparse matrix to be added is symmetric. In this case
			/// the value also needs to be added at the transposed location in
			/// the matrix because PETSc is using the full profile, also for symmetric matrices
			if (matrix.getSparseMatrixType() == _symmetric && index(0) != index(1))
			ierr = MatSetValue(this->petsc_matrix_wrapper->mat, index(1), index(0), val_to_add, ADD_VALUES); CHKERRXX(ierr);
			}

			this->performAssembly();
			}

			/* -------------------------------------------------------------------------- */
			/**
			* Method to add another PETSc matrix to this PETSc matrix
			* @param matrix PETSc matrix to be added
			* @param alpha the factor specifying how many times the matrix should be added
			*/
			void PETScMatrix::add(const PETScMatrix & matrix, Real alpha) {
			PetscErrorCode ierr;

			ierr = MatAXPY(this->petsc_matrix_wrapper->mat, alpha, matrix.petsc_matrix_wrapper->mat, SAME_NONZERO_PATTERN); CHKERRXX(ierr);


			this->performAssembly();
			}

			/* -------------------------------------------------------------------------- */
			/**
			* MatSetValues() generally caches the values. The matrix is ready to
			* use only after MatAssemblyBegin() and MatAssemblyEnd() have been
			* called. (http://www.mcs.anl.gov/petsc/)
			*/
			void PETScMatrix::performAssembly() {
			PetscErrorCode ierr;
			ierr = MatAssemblyBegin(this->petsc_matrix_wrapper->mat, MAT_FINAL_ASSEMBLY); CHKERRXX(ierr);
			ierr = MatAssemblyEnd(this->petsc_matrix_wrapper->mat, MAT_FINAL_ASSEMBLY); CHKERRXX(ierr);
			}

			/* -------------------------------------------------------------------------- */
			/**
			* Method is called when the static solver is destroyed, just before
			* PETSc is finalized. So all PETSc objects need to be destroyed at
			* this point.
			*/
			void PETScMatrix::beforeStaticSolverDestroy() {
			AKANTU_DEBUG_IN();

			try{
			this->destroyInternalData();
			} catch(...) {}

			AKANTU_DEBUG_OUT();
			}

			/* -------------------------------------------------------------------------- */
			/// destroy all the PETSc data structures used for this matrix
			void PETScMatrix::destroyInternalData() {
			AKANTU_DEBUG_IN();

			if(this->is_petsc_matrix_initialized) {

			PetscErrorCode ierr;

			ierr = MatDestroy(&(this->petsc_matrix_wrapper->mat)); CHKERRXX(ierr);
			delete petsc_matrix_wrapper;

			this->is_petsc_matrix_initialized = false;
			}

			AKANTU_DEBUG_OUT();
			}


			/* -------------------------------------------------------------------------- */
			/// access K(i, j). Works only for dofs on this processor!!!!
			Real PETScMatrix::operator()(UInt i, UInt j) const{
			AKANTU_DEBUG_IN();

			AKANTU_DEBUG_ASSERT(this->dof_synchronizer->isLocalOrMasterDOF(i) && this->dof_synchronizer->isLocalOrMasterDOF(j), "Operator works only for dofs on this processor");

			Array<Int> index(2,1);
			index(0) = this->dof_synchronizer->getDOFGlobalID(i);
			index(1) = this->dof_synchronizer->getDOFGlobalID(j);
			AOApplicationToPetsc(this->petsc_matrix_wrapper->ao, 2, index.storage());

			Real value = 0;

			PetscErrorCode ierr;
			/// @todo MatGetValue might be very slow for MATBAIJ, might need to use MatGetValuesBlocked
			ierr = MatGetValues(this->petsc_matrix_wrapper->mat, 1, &index(0), 1, &index(1), &value); CHKERRXX(ierr);


			AKANTU_DEBUG_OUT();


			return value;

			}

			/* -------------------------------------------------------------------------- */
			/**
			* Apply Dirichlet boundary conditions by zeroing the rows and columns which correspond to blocked dofs
			* @param boundary array of booleans which are true if the dof at this position is blocked
			* @param block_val the value in the diagonal entry of blocked rows
			*/
			void PETScMatrix::applyBoundary(const Array<bool> & boundary, Real block_val) {
			AKANTU_DEBUG_IN();

			PetscErrorCode ierr;

			/// get the global equation numbers to find the rows that need to be zeroed for the blocked dofs
			Int * eq_nb_val = dof_synchronizer->getGlobalDOFEquationNumbers().storage();

			/// every processor calls the MatSetZero() only for his local or master dofs. This assures that not two processors or more try to zero the same row
			UInt nb_component = boundary.getNbComponent();
			UInt size = boundary.getSize();
			Int nb_blocked_local_master_eq_nb = 0;
			Array<Int> blocked_local_master_eq_nb(this->local_size);
			Int * blocked_lm_eq_nb_ptr = blocked_local_master_eq_nb.storage();

			for (UInt i = 0; i < size; ++i) {
			for (UInt j = 0; j < nb_component; ++j) {
			UInt local_dof = i * nb_component + j;
			if (boundary(i, j) == true && this->dof_synchronizer->isLocalOrMasterDOF(local_dof)) {
			Int global_eq_nb = *eq_nb_val;
			*blocked_lm_eq_nb_ptr = global_eq_nb;
			++nb_blocked_local_master_eq_nb;
			++blocked_lm_eq_nb_ptr;
			}
			++eq_nb_val;
			}
			}
			blocked_local_master_eq_nb.resize(nb_blocked_local_master_eq_nb);


			ierr = AOApplicationToPetsc(this->petsc_matrix_wrapper->ao, nb_blocked_local_master_eq_nb, blocked_local_master_eq_nb.storage() ); CHKERRXX(ierr);
			ierr = MatZeroRowsColumns(this->petsc_matrix_wrapper->mat, nb_blocked_local_master_eq_nb, blocked_local_master_eq_nb.storage(), block_val, 0, 0); CHKERRXX(ierr);

			this->performAssembly();
			AKANTU_DEBUG_OUT();
			}

			/* -------------------------------------------------------------------------- */
			/// set all entries to zero while keeping the same nonzero pattern
			void PETScMatrix::clear() {
			MatZeroEntries(this->petsc_matrix_wrapper->mat);
			}

			__END_AKANTU__

rAKA/src/solver/petsc_matrix.cc7dd9648d4655features/30-implementin…

petsc_matrix.ccView Options

rAKA/src/solver/petsc_matrix.cc
7dd9648d4655features/30-implementin…

petsc_matrix.cc
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